What wing profile should I use ?
I'm planning to build a model of a Polish glider PW-5 in 1:5 scale.
I would like to ask you what profile should I use?
I'm not sure if the profile from this image is good or not.
Nice subject! yyz or Erich here on RCAeroTowing are good for airfoil advice. Guys?
As I said, nice subject...
Let's take a stab at this. So the mighty, Arcus-eating PW-5 has a 13 meter span. That in 1:5 scale is 2.6 meters which is getting pretty small (both in terms of span and average chord).
How about jumping up to 1:4 or 1:3 scale? I think you'd end up with a much nicer, and likely easier, plane to fly. At one of those sizes, this airfoil would probably work well:
The MH-32 is also a good all-around airfoil but needs to be thickened up in this case:
If you're absolutely set on 1:5 scale, then I would spend some time on the ICARE and SoaringUSA sites and look for gliders in that same 2.5 to 3 meter size and see which airfoils they're using.
You need to also consider how heavy you expect the finished glider to be and what kind of construction techniques you plan to use on the wing. Personally, I wouldn't try to go below 10% thickness of chord.
There are a lot of smart people on this site and you'll likely get good advice.
Hope that helps a little bit,
Last edited by yyz; 08-08-2012 at 01:19 AM.
You might want to check out the Little Soaring Fleet of Poland site http://mysite.verizon.net/vze2qbfc/id2.html . In the description of the 1/5 the scale Pirat it specs a Quabeck 2.5/12. Also look at the Super Scale R/C models page for a 3.5 scale PW-5. At 1/5 th scale it will very important to keep the plane very light unless you want a slope lead sled.
I found this --> http://www.drexpol-modele.com.pl/ind...lep&artykul=16
And they use wings profile HQ 3/13, maybe this be good.
Who know, what kind of wing profile it is ?
This profile used in PW-5 plans.
NN 18-17. I thought everyone knew that!
And in case you are wondering, not a good choice for a 1:5 scale plane.